Legal Claims and Third-Party Privacy

Recently I published here a case comment on a Quebec tribunal decision involving the admissibility of social media evidence.

One particular element of the argument surprised me, and I would be interested in your views.

In the case, an employee brought a complaint before a labour tribunal against her employer, claimed that the employer had created, or allowed to continue, an atmosphere of harassment. As evidence, she brought printouts of comments made by her work colleagues on the Facebook page of another colleague who was also (for a while) a Facebook friend of the complainant.

The employer objected to this evidence, among other reasons, because it infringed on the privacy interests of the employees who made those comments.

Does this make sense to you, that the employer would have standing to invoke the privacy interests of third parties? What relevance is their privacy to the dispute between the employer and the employee? If a claim depends on what someone else said, can the claimant be prevented from proving it out of some kind of legal right to privacy of the people who said it? (Note that whether this is hearsay evidence is a separate question, also argued in the case.)

For that matter, could the third parties intervene to object to their words being used, as an infringement on their privacy? Would it be appropriate for the tribunal to raise their privacy interests on its own motion?

Is evidence ‘improperly obtained’ just because it violates the privacy interests of the person whom it concerns? Could use of such privacy-violating evidence ‘bring the administration of justice into disrepute’ so the evidence should be excluded?

Does it depend on how it was obtained? I suppose if one got the evidence by wiretap or other illegal or distasteful method, a court could refuse to admit it on that ground, just as it would do for tangible evidence obtained the same way. But when is ‘privacy’ on its own a sufficient ground to exclude relevant evidence?

In the instant case, the tribunal held that the commenters had no expectation of privacy for comments on Facebook with respect to the class of ‘friends of friends’ that could be almost infinite. My question is broader: even if they had had an expectation of privacy, could that expectation prevail over a claim that needed the evidence?

What are the limits, or even the rules, here?

This is not the same issue as whether ‘private’ information (on Facebook or elsewhere) has to be disclosed by a party to litigation, in the discovery process. Third parties are not subject (in Canada) to discovery.

My note mentioned a provision of the rules of procedure of the tribunal that barred evidence that violated fundamental rights (of anybody, apparently), and a section of the Manitoba Privacy Act that bars the use in any civil proceeding of any evidence obtained by a breach of privacy as defined in the Act. Is such a provision common, and should it be?

How would that affect, say, defamation cases? Sometimes defamation is in a conversation that the person defamed was not intended to overhear. Could the evidence be excluded because the plaintiff should not have been listening? (The defendant in that example would be a direct party, not a ‘third party’. Has anyone in this scenario a maintainable privacy interest that could be invoked in the proceeding?)